After watching an interview of James conducted by Lemon at the I Promise School in Akron, a school for at-risk children, Trump tweeted:

"LeBron James was just interviewed by the dumbest man on television, Don Lemon. He made LeBron look smart, which isn't easy to do. I like Mike!" the president tweeted. The Mike he referred to in the tweet was not Vice President Mike Pence.

Perhaps no other public figure since comedian Redd Foxx has made more frequent use of the words "dumb" or "dummy" to insult others. Trump's Twitter rants belittling the IQs and physical characteristics of people with whom he disapproves are well-known penchants of the president.

Trump, who has called himself a "stable genius," truly seems to derive enormous pleasure from calling other people dumb. If one buys the notion that with great power comes great responsibility, Trump is without a doubt the most immature and dangerous senior citizen in America.

In response to the tweet, James opted for the high road, at least for now, but Don Lemon unloaded on the president Monday evening.

"Let me not mince words here. This president traffics in racism and is fueled by bullying." The CNN anchor also called the tweet an example of "one of the oldest canards of America's racists past and present - that black people are of inferior intelligence."

Trump may be a racist. Much of his behavior is indefensible. However, racism is an easy charge to level but a more difficult charge to prove. I've heard tortured cases made that Trump is more racist than many of America's former slaveholding presidents.

His latest "dummy" tweet hardly serves as confirmation of his racism. It clearly demonstrates, however, that Trump happily brandishes the playground insult like a childish cudgel and generally gets the result he seeks: attention.

Truth of the matter is Donald Trump sees "dumb" people in all races and genders. If someone disagrees with him and has a substantial platform to air their disagreement, chances are this president thinks that person is a dummy and he enjoys labeling them as such.

First Lady Melania Trump offered a surprising retort to her husband when her spokeswoman issued a statement on her behalf following the uproar over the president's tweet. She offered praise for the NBA icon and philanthropist:

"It looks like LeBron James is working to do good things on behalf of our next generation and just as she always has, the first lady encourages everyone to have an open dialogue about issues facing children today," the spokeswoman said in a prepared statement.

The spokesperson later clarified the statement to make it clear that Melania Trump was not taking sides in her husband's Twitter wars. The fact that she spoke out, however, offers some evidence that the first lady takes seriously her announced initiative to address bullying - in all of its forms.

Trump is far from the first U.S. president to attract criticism for minimizing the intelligence of others. One can only imagine what President Lyndon Johnson would have been like if Twitter had existed during his administration.

Johnson once offered this tactless observation of future President Gerald Ford: